No boost

[davring]

Hello all, Newbie here. Read through your forum and did a couple of searches and could not find a definitive answer. I have a stock 97 Riviera SC with 39,800 original miles. (purchased from original owner, my Mom!) and the boost has dropped to virtually zero. The car runs perfectly and yes the belt is on and not slipping I did a quick check of all vacuum controls/hoses and see no problem. Everything is like new under the hood, only dusty. This happened all of a sudden, so I suspect something failed, but no check engine light, and again it runs fine. I checked All-Data, at a Friends garage, and they have virtually no information on the control circuits/system. Any ideas? Thanks in advance for any ideas as the where to start.

Dave

 

[notacarlo]

So it drives normally? When you say "no boost" is that the gauge telling you there's no boost, or is the car accelerating like a toyota tercel and otherwise running normal?

 

[davring]

So it drives normally? When you say "no boost" is that the gauge telling you there's no boost, or is the car accelerating like a toyota tercel and otherwise running normal?

It drives like a 3.8 Buick w/o a supercharger, better than a Tercel, I hope!. There is no gauge, and yes it does start and drive as well as it ever has. Mileage is normal, but low RPM torque and midrange power is way off. Just returned from a short trip and hyway acceleration requires stepping on it hard enough to drop to third gear, it used to pull hard at lower RPM's.